Film unwinding method

ABSTRACT

A method in which moisturized air is impinged against the end of a roll of hydrophilic film to provide for smooth and continuous edge separation of overlying film convolutions during the unwinding thereof. The moisturized air is comprised of extremely fine particles of water which are suspended in a moving air stream and which are present in only such amounts as to avoid water from accumulating and discharging as droplets from the impinged end of the film roll.

United States Patent 2 191 Pepmeier et a1.

mi 3,822,043 [451 July 2,1974

1 1 FILM UNWINDING METHOD [75] Inventors: Carl Pepmeier; David C. Burks,

both of Fredericksburg, Va.

[73] Assignee: FMC Corporation, Philadelphia, Pa.

[22] Filed: Mar. 31, 1972 [21] App]. No: 240,050

521 US. Cl...' .Q 242/55, 271/105 511 Int. Cl B65h 75/02 [58] Field of Search 242/55, 67.2, 67.3;

[56] References Cited 7 UNITED STATES PATENTS 1,498,966 6/1924 Henderson".. 271/26 R 1,718,581 6/1929 Rockstroh 271/26 R Upham 271/26 R 3,359,128 12/1967 Humphrey .r 242/78.1 3,425,686 2/1969 Leibold 271/105 3,467,331 9/1969 Pcpmeier 242/55 Primary Examiner-John W. Hucrkert Assistant EtaminerEdward J. McCarthy 5 7] ABSTRACT A method in which moisturized air is impinged against the end of a roll of hydrophilic film to provide for smooth and continuous edge separation of overlying film convolutions during the unwinding thereof. The

moisturized air is comprised of extremely fine parti- C1S of water which are suspended in a moving air stream and which are present in only such amounts as to avoid water from accumulating and discharging as droplets from the impinged end of the film roll.

3 Claims, 3 Drawing Figures The present invention is directed. to unwinding of film from a roll and, more particularly, to a method for effecting smooth and continuous separation of overlying convolutions of hydrophilic film during the unwinding thereof. 7

During the unwinding of hydrophilic films, such as cellophane, from supply rolls the separation of overly,- ing film convolutions is often erratic. resulting in a pulsating or intermittent delivery of film from such rolls and, in. more extreme instances, causing the film to rupture. While this erratic behavior is obviously due to adherence between the overlying convolutions in the film roll, it is experienced with both coated and uncoated hydrophilic films.

The adherence between overlying convolutions of hydrophilic film is concentrated along one or both longitudinal edges of the wound film, and is apparently due to deformations existing along at least portions of one or both ends of the film roll. Such deformations may be, for example, scoring or indentations impressed into the end of the film roll as when the end of such roll I is inadvertently struck or rubbed against or, by some rigid object. Damage of this nature to the end of a roll of hydrophilic film may also occur when the roll rests on one end thereof during transit and/or storage, or when such roll is tilted along its edge preparatory to its movement to or from such end rest position. 1

A primary object of this invention is to provide a genthe presentinvention, with the moisturized air issuing therefrom in the form of an expanding cone.

Generally, the stream of moisturized air directed toward the end of the roll of hydrophilic film is not perceptible to the eye'and thus the concentration of water within such stream need be remarkably low to achieve the objectives of the present invention. Upon impinging erally new or improved and more satisfactory method ing convolutions of cellophane film from rolls having deformations along at least one'end thereof.

A further object is a method for effecting smooth and continuous separation of edge portions of overlying convolutions of non-fibrous hydrophilic film during the unwinding thereof from a roll. I

A still further object of this invention is the provision of an improved method for unwinding of hydrophilic film. which method is simple, involves little investment and operating expense and does not alter the physical or chemical characteristics of the hydrophilic fil which is treated.

The above and other. objects of this invention are achieved by a method in which moisturized air is conagainst the end of the hydrophilic film and serving its intended purpose, the water in such moisturized air is rapidly and readily assumed by the surrounding ambient atmosphere so that little, if any, water collects on the end of the film roll. 1

Impinging dry air against the end of the roll of hydrophilic film does not provide for the beneficial results which are achieved with the method of the present invention. Similarly, the force with which the moisturized air impinges against the end of the roll of hydrophilic film does not significantly enhance separation of the overlying film convolutions. Thus, it is believed but not definitely established that the advantages provided by the method of the present invention are due perhaps to the water in the moisturized air stream causing a slight swelling of the hydrophilic film along its edgesand thereby encouraging separation of overlying film convolutions and/or to the lubricity of such water.

In the drawing,

FIG. 1 illustrates one end ofa roll of hydrophilic film as his treated in'accordance with the method of the present invention during the unwinding thereof;

FIG. 2 is a plan view of the roll and film treating apparatus shown in FIG. I; and

FIG. 3, a perspective view of one end of the film roll and its adjacent treating apparatus.

With reference to the drawing, character ll refers to a hydrophilic film, such as cellophane, which is wound as roll 13 on a supporting core 15. Deformations, such as scoring, along one end of the roll' 13 are indicated by lines 17, 19and 21 and, for purposes of, description, it

tinuously impinged against at least one and more pr'eferably both ends of a roll of hydrophilic film during the unwinding thereof to provide for smooth and continu-. ous separation of overlying film convolutions. This moisturized air is comprised of extremely fine particles of water which are'suspended in an air stream flowing.

' toward the end of the rollof film. The amountof water is assumed that similar deformations are impressed in the opposite end of the rolll3.

As illustrated in FIG. 1, the film 11 is unwound from the roll 13 passed beneath a guide roll 23 and delivered to other apparatus, not shown, as for example, for printing or laminating, or packaging, etc.

In accordance with the method of the present invention, during this unwinding of the film 11, moisturized air from atomizers 25 and 27 is continuously impinged against opposite ends of the roll 13. The atomizers 25 and 27 are of conventionalconstruction, with each ineluding conduit29 connected to a source of air under pressure and a similar conduit 31 leading from a water supply.

.As heretofore mentioned, the amount of water necessary for achieving the objectives of the present invention is extremely smalland thus the delivery of such waterto the atomizers does require some control. The

' water which. is delivered to the atomizers is broken into extremely fine particles by the air passing therethrough, which particles are continuously carried by such air as expandingcones 33 toward and intocontact with the end of the roll 13.

As best shown in FIG. 3, the cones 33 of moisturized air are preferably impingedagainst the opposite ends of the roll 13 only along those areas at which separation of the film 11 fromsuch roll 13 is takingplace. With aminimal amount of water being applied to the ends of the roll 13, the atmosphere aroundthe roll rapidly assumes the same so that little, if any, water accumulates on the roll 13 or travelling film 11.

[t is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined in the appended claims.

We claim:

1. A method for effecting smooth and continuous edge separation of overlying convolution of a roll of hydrophilic film during the unwinding thereof including the step of impinging moisturized air against at least one end of the wound roll of hydrophilic film continuously during the unwinding thereof and at least in the area at which overlying film convolutions are being separated from each other, said moisturized air being comprised of extremely fine particles of water which are suspended in an air stream flowing toward the end of the roll of film and which are present in only such amounts as to avoid water from accumulating and discharging as droplets from the impinged end of of the film roll.

2. A method as defined in claim 1 wherein the moisturized air, from the point of delivery to the location of impingement with the end of the film roll, is in the form of an expanding cone.

3. A method as defined in claim 1 wherein moisturized air. is impinged against both ends of the roll of hydrophilic film. 

1. A method for effecting smooth and continuous edge separation of overlying convolution of a roll of hydrophilic film during the unwinding thereof including the step of impinging moisturized air against at least one end of the wound roll of hydrophilic film continuously during the unwinding thereof and at least in the area at which overlying film convolutions are being separated from each other, said moisturized air being comprised of extremely fine particles of water which are suspended in an air stream flowing toward the end of the roll of film and which are present in only such amounts as to avoid water from accumulating and discharging as droplets from the impinged end of of the film roll.
 2. A method as defined in claim 1 wherein the moisturized air, from the point of delivery to the location of impingement with the end of the film roll, is in the form of an expanding cone.
 3. A method as defined in claim 1 wherein moisturized air is impinged against both ends of the roll of hydrophilic film. 